Biological Hierarchies and Various Mutations in Genome Sequences

One of the most remarkable phenomena in biology is higher evolution of organisms such as domains and kingdoms. How the genome sequence changed during the birth of a new domain, kingdom, or phyla of an organism is one of the major questions. The purpose of this chapter is to estimate how the physical properties of proteins in the genome sequence relate to the higher taxa of organisms. We first focused on the distribution of charges, a long-range interaction. We converted all amino acid sequences from the genome sequence into charge sequences and calculated their autocorrelation functions. As a result, we observed a remarkable charge periodicity of 28 residues only in vertebrates. This indicates that vertebrates can be accurately classified from their genome sequences alone. Furthermore, an exclusive feature was observed between prokaryotes and eukaryotes in the charge distribution of all amino acid sequences. Namely, in the autocorrelation function of the charge sequences, a long-tailed positive correlation was observed only in eukaryotes. In general, we know that many types of mutations exist in the genome sequence and found that the insertion and duplication of long DNA sequences are closely related to the higher hierarchy of organisms.